package com.hmdp.service.impl;

import cn.hutool.core.util.StrUtil;
import cn.hutool.json.JSONUtil;
import com.hmdp.entity.ShopType;
import com.hmdp.mapper.ShopTypeMapper;
import com.hmdp.service.IShopTypeService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.utils.RedisConstants;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import java.util.List;
import java.util.concurrent.TimeUnit;

/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Service
public class ShopTypeServiceImpl extends ServiceImpl<ShopTypeMapper, ShopType> implements IShopTypeService {

    @Resource
    private StringRedisTemplate stringRedisTemplate;
    /**
     * 获取类型列表
     * @return
     */
    @Override
    public List<ShopType> getTypeList() {
        //1.从redis查询
        String key = RedisConstants.SHOP_TYPE_KEY;
        String typeJson = stringRedisTemplate.opsForValue().get(key);
        //2.判断是否存在
        if (StrUtil.isNotBlank(typeJson)) {
            //3.存在，直接返回
            return JSONUtil.toList(typeJson, ShopType.class);
        }
        //4.不存在，查询数据库
        List<ShopType> typeList = this.list();
        //5.不存在，返回空列表
        if (typeList.isEmpty()) {
            return List.of();
        }
        //6.存在，写入redis
        stringRedisTemplate.opsForValue().set(key, JSONUtil.toJsonStr(typeList),RedisConstants.CACHE_SHOP_TTL, TimeUnit.MINUTES);
        return typeList;
    }
}
